This application claims priority to Spanish Patent Application No. 200001822 filed Jul. 21, 2000.
The present invention relates to an all-terrain vehicle, such as those popularly known as xe2x80x9cmulesxe2x80x9d, which despite their small size have a large load capability and are operational in all terrains.
The object of the invention are a number of improvements which increase its versatility and improve its performance.
All-terrain vehicles commonly known as xe2x80x9cmulesxe2x80x9d have a sturdy, compact chassis which rests on four wheels, all of which are driven, and have a small loading platform which, despite its small size, can carry large loads, on the order of 400 to 800 Kgs.
In these type of vehicles all-terrain operativity usually prevails over speed, so that they are usually quite slow and often have top speeds between 5 and 40 Km/h. For this same reason they are generally sturdy, simple vehicles, with minimal comfort for the driver, often lacking a cab, power steering, windshield wipers, heating, etc., justifying their popular name of xe2x80x9cmulesxe2x80x9d. In fact, their origin lies in providing a mechanical substitute for these animals in handling and transporting large loads in environments where ordinary all-terrain vehicles cannot operate.
The all-terrain vehicle of the invention substantially improves the operational characteristics of current vehicles, as well as providing a number of additional advantages which will be described throughout the description.
For this purpose, based on the general basic structure of this type of vehicle as regards chassis, engine, suspension, traction and steering, one of the main characteristics of the vehicle disclosed is that it incorporates on its loading platform several longitudinally aligned rollers, which are mounted on corresponding supports which when set on said platform can occupy two extreme positions. In the first of these positions the rollers do not project beyond the loading platform, so that this surface is flat and practically horizontal. In the second, the structure that contains the rollers can be raised with them, thereby raising the load which may be on the platform. Thus, as the load rests on the rollers of the two or more rows it can move longitudinally to be correctly positioned on the plate, or for unloading.
The vehicle is provided on the rear generator line of the load plate with strong points on which hinges connected to a flat structure may be joined. This flat structure is generally flat, rectangular and similar in width to the loading platform. This extra hinged surface provides the following additional functions:
a) When it is in a horizontal position the loading surface of the vehicle is increased.
b) When it is vertical and facing downwards it provides the vehicle with a 90xc2x0 outlet angle. If there is no need for the vehicle to have an outlet angle of 90xc2x0 this additional hinged loading surface can be fixed in place, and incorporated into the loading platform of the vehicle. If a greater loading surface is required this additional structure can be removed, so that its extra weight may be replaced by additional useful load.
This complement is secured in its working position, as a complement of the loading platform (horizontal position) and in its resting position (vertical downwards) by suitable attachment elements, as described further below.
In accordance with a further characteristic of the invention, the mid area of the loading platform is provided, between the aligned rollers described above, with a two-leaf door with both leafs padded on the bottom surface and able to rotate 180xc2x0 about two-shaft hinges. These doors open outwards and may occupy two stable positions, namely:
a) Closed position: In this position the doors are a continuation of the loading platform and have a specific load strength which is identical to that of the loading platform;
b) Open position: The object of this position is to allow transportation of passengers. In this position the doors are rotated 180xc2x0 with respect to the previous position, and rest entirely on the fixed part of the platform. Its padded surface faces upwards, revealing a central receptacle for the passengers"" legs.
The vehicle is provided with two elongated plates, generally made from a lightweight material so that it is easier to handle, designed such that:
a) One end of its short side is bevelled
b) The end opposite the bevelling of the short side has two hooks with a special design, which will be described later
c) One side wall of the wide side has two hooks such as those of the previous paragraph.
These plates have several functions:
a) The rear area of the loading platform is provided with forks onto which the hooks of b) above can couple perfectly, thereby forming a safety buckle. With the plates in this position and allowing their bevelled end to rest on the floor, ramps are provided between the loading platform and the floor, which fulfil two functions:
1. They allow to pile one vehicle on top of another.
2. Together with the above described retractable rollers, they allow loading and unloading between the loading surface and a flat bed pallet. Loading is performed with the aid of a winch which may be placed on the loading platform behind the driver""s position. Unloading is performed simply by pushing the load manually, so that it slides on the rollers. Thus, a single person can handle loads of one ton easily.
b) Each sidewall of the loading platform has forks which are similar to those on its rear and which couple perfectly onto the hooks described in point c) above. The plates can lock onto these forks in two positions:
1st position: The plate is stable and horizontal, forming a continuation of the loading platform with a similar specific load capacity.
2nd position: The plate is vertical, thereby forming sidewalls for the loading platform. These can be very useful when transporting loose loads, in which case the system is completed by straps attached to one of the sides of the vehicle""s roll bar which lock onto the plates on their outside and continue as far as the other side of the roll bar. These straps are normally provided with a tension device. We thus have a fully closed loading surface, with a plate on each side, two straps on the rear and the structure of the roll bar on the front.
c) The plates can further be helpful in particularly demanding traction conditions, such as viscous mud, loose sand, etc.
When loose loads are carried and it is known in advance that the plates will not be required for other purposes, the plates may be replaced by four struts designed such that they insert in corresponding orifices made in the edges of the loading platform, so that they remain vertical, thus forming sidewalls. These struts have handles through which may pass strong straps which are attached to one side of the roll bar, and which then pass though the handles of the four struts, to be finally attached to the other side of the roll bar. Thus, an enclosure is obtained with two straps on each side of the loading platform and on its rear, with the front area closed by the roll bar.
The vehicle is designed so that it may have a winch attached in six different positions, depending on the various electrical power connections so that the winch may be powered more easily in each operational position. These positions are:
Centred on the loading platform and held between this platform and the roll bar. This is to allow loading from the ground at a controlled speed, with the aid of the aforementioned plates.
One on each side of the vehicle, i.e. forward, rear, left and right. This flexibility in the position of the winch greatly simplifies mobility in difficult terrain, increasing safety in the manoeuvre. It also increases capacity for recovering other vehicles.
Transportation position.
The vehicle""s kinematic chain can be adapted to various uses, so that its top speed can be set between 45 and 90 km/h and its maximum tractive force at the wheel can be between 1600 daN and 3200 daN.
To improve its all-terrain performance the vehicle has axle differentials which are 100% lockable by a pneumatic automatic device. This operation can be performed with the vehicle in motion.
Naturally, the locking sequence must be as follows:
1. Locking the rear differential.
2. Once the rear differential is locked the front differential can be locked (if operational conditions suggest that it is not sufficient to lock the rear differential, and maintaining the forward differential locked only for the time required to overcome the difficulty).
In order to unlock the differential the inverse process must be followed, that is:
1. Unlock the forward differential (if it is locked).
2. Unlock the rear differential.
The compressor used to lock/unlock the differentials is also used to inflate the tires.
The vehicle also allow the central differential to be free, self-locking or limited sliding.
The vehicle is designed such that it has attack and outlet angles of 90xc2x0 and a between-axle central clearance of 400 to 440 mm.
The vehicle has long-run suspensions in order to allow the wheels to remain in contact with the ground in a maximum of conditions, which together with the aforementioned possibility of locking the differentials provides outstanding all-terrain performance.
The vehicle is provided with a tow hitch on the rear and is designed to tow loads.
The vehicle is also provided with hooks on the entire periphery of the loading platform, in order to hold down the load whatever its configuration. It also has additional hooks for raising it with slings.
The vehicle may have no cab, or have a simple windshield and a tarp, or may have a fully closed cab.
Finally, and according to a further characteristic of the invention, the vehicle steering wheel is removable, and the roll bar and seat can be folded forwards. Thereby a position is obtained in which they are barely above the general plane of the loading platform of the vehicle, which allows a simple piling of two vehicles in order to minimise the space occupied by them during storage, transportation of airlifting.
One possible use of the vehicle is to aid in the distribution of goods of international aid given by some countries to others in specific situations of need. A convenient condition for this use is its possibility of airlifting, parachute launching and wading. Therefore, the vehicle is designed to operate in these conditions, with the following characteristics:
For airlifting:
The chassis and all of its components withstand the following dynamic loads:
Forward 3.0 g.
Rearward 1.5 g.
Lateral 1.5 g.
Vertical 2.0 g.
For launching:
1. Withstand dynamic loads which occur during extraction of the equipment from the airplane, on the corresponding pallet.
2. Withstand after extraction the first pendulum action, with an amplitude of nearly 270xc2x0 from the horizontal, so that during part of this oscillation the vehicle will be inverted, with the wheels facing upwards.
3. The entire structure and components are designed to withstand ground impact, which is equivalent to a free drop from a height of 3.5 meters.
For wading:
The vehicle is designed to wade in up to 70 cm. depths without any special preparation, with all water-sensitive components placed above this level.